Household appliances use heat sources to generate heat for various purposes. For example, dishwashers, laundry washers, and laundry dryers use heat sources to dry articles such as dishes and clothing. In another example, some refrigerators and freezers use heat sources during defrost cycles to remove frost buildup in the freezer. Typical appliances use concentrated high wattage heaters and use fans or blowers to distribute the heat to desired locations. This results in uneven heat distribution in the appliance.